Akodu 2017.

Study characteristics
Methods	Study design: RCT Setting: Nigeria, healthcare Exercise groups: 4 Comparison groups: 0
Participants	Number of participants: 74 (E1 = 18, E2 = 18, E3 = 20, E4 = 18) Chronic LBP duration: Not specified (not specified) Neurological/radicular symptoms: No participants Mean age (years): 48 Sex (female): 47%
Interventions	Exercise Group 1 (E1): Muscle energy technique: undefined posture held against therapist resistance to promote relaxation of the other muscle in the antagonistic pair; type = stretching & strengthening; duration = 8 weeks; dose = low; design = standardised; delivery = individual; additional intervention = none Exercise Group 2 (E2): Core stabilisation; type = core strengthening; duration = 8 weeks; dose = low; design = standardised; delivery = individual; additional intervention = none Exercise Group 3 (E3): Muscle energy technique, core stabilisation; type = stretching & core strengthening; duration = 8 weeks; dose = low; design = standardised; delivery = individual; additional intervention = none Exercise Group 4 (E4): Educational booklet and conventional stretches; type = stretching; duration = 8 weeks; dose = low; design = standardised; delivery = individual; additional intervention = advice/education
Outcomes	Core outcomes reported: Pain (Visual Analogue Scale); function (Oswestry Disability Index) Follow‐up time periods available for syntheses: 8 weeks (short)
Notes	Conflicts of interest: Not reported Funding source: Not reported Other: Information modified for author contact
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Randomisation was accomplished "via a computer‐generated random number sequence".
Allocation concealment (selection bias)	High risk	No information on treatment allocation concealment
Blinding of participants and personnel (performance bias) All outcomes	Low risk	1. Patients could not be blinded to allocation due to the nature of the treatments. 2. All 4 arms received some level of activity in their treatment and novel interventions would not be easily accessible outside of the study setting.
Blinding of care provider (performance bias)	High risk	1. Care providers could not be blinded to allocation due to the nature of the treatments; 2. Lack of care provider blinding may have caused deviations from intended intervention, as providers had significant contact with all treatment groups, and different expectations of groups' efficacies; 3. If lack of care provider blinding did cause deviations from intended interventions, these deviations would not have been balanced because of different expectations of groups' efficacies; 4. If lack of care provider blinding did cause deviations from intended interventions, we expected overestimation of "better" groups' outcomes and underestimation of control group.
Blinding of outcome assessment (detection bias) All outcomes	High risk	1. Outcome assessors for this study were the patients themselves, who could not be blinded to allocation due to the nature of the treatments; 2. Pain and functional questionnaires are subjective, and responses could be altered by awareness of intervention; 3. Muscle energy technique is a relatively novel sounding intervention and some patients may have higher expectations for it than the other interventions.
Incomplete outcome data (attrition bias) All outcomes	Low risk	1. Dropout rate was 7% (5/74).
Participants analysed in group allocated (attrition bias)	Low risk	1. Not explicitly stated but no indication that patients were analysed otherwise; numbers matched up for analysis and allocation.
Selective reporting (reporting bias)	Low risk	1. No linked protocol or statistical analysis plan found: within this publication all outcomes and analyses fully reported; no obvious omissions
Groups similar at baseline (selection bias)	High risk	Baseline similarity between groups on age, body mass index and pain; function was not similar, sex distribution was suspiciously not reported by group, and duration of symptoms was not measured.
Co‐interventions avoided or similar (performance bias)	Low risk	No mention of co‐interventions in the study
Compliance acceptable in all groups (performance bias)	Low risk	All patients completed the study; seemed indicative of all patients followed up; not all patients completed every session; no information on compliance
Timing of outcome assessment similar in all groups (detection bias)	Low risk	1. All outcome assessments were identical regardless of treatment group 2. Visual Analogue Scale (for pain) and Oswestry Disability Index (for function) are well‐validated tools in the low back pain context.
Other bias	Low risk	Appeared free from other sources of bias